Air conditioning device for vehicle

Abstract

Provided is a vehicle air conditioning device with a simple structure which can quickly raise the temperature of engine cooling water used for heating the air in a vehicle cabin in an engine start period in a low ambient temperature. The vehicle air conditioning device comprises the following elements integrally connected with each other: a first water heat exchanger ( 26 ) provided in the middle of a passage through which an engine cooling water flows from the water jacket of an engine ( 3 ) to a heater core ( 8 a ), a second water heat exchanger ( 27 ) provided in the middle of a passage through which the engine cooling water flows from the heater core ( 8 a ) to the water jacket of the engine ( 3 ), and a first external heat exchanger ( 18 ) for refrigerant condensation provided between the first and second water heat exchangers ( 26, 27 ). In the engine start period in a low ambient temperature, the engine cooling water flowing from the water jacket to the heater core ( 8 a ) is heated by heat released from the first external heat exchanger ( 18 ) to rise in temperature.

1 . A vehicle air conditioning device comprising:
 a refrigerant circulating passage arrangement for air cooling through which refrigerant is circulated among a compressor, a condenser for refrigerant condensation outside a vehicle cabin, a first inflation and depressurization means, an evaporator for air cooling and liquid refrigerant evaporation inside the vehicle cabin and an accumulator in this order;   a cooling water circulating circuit for air heating configured to circulate cooling water between a heater core;   a bypass passage connected in parallel with the condenser and the evaporator and connected with the compressor via the accumulator;   a switching valve configured to switchably make a refrigerant discharge opening of the compressor communicate with either the condenser or the bypass passage; and   a heat exchange means for heating water comprising a water heat exchange means disposed in the middle of a passage to the heater core and a refrigerant heat exchange means disposed in the middle of the bypass passage to transfer/receive heat to/from the water heat exchange means, wherein:   the refrigerant heat exchange means comprises a heat exchange means for refrigerant condensation provided in series in the middle of the bypass passage and a second inflation and depressurization means configured to inflate the refrigerant condensed by the heat exchange means for refrigerant condensation;   the water heat exchange means comprises a water heat exchanger configured to flow cooling water to the heater core; and   the heat exchange means for refrigerant condensation is configured to be able to heat the cooling water in the water heat exchanger.   
     
     
         2 . A vehicle air conditioning device according to  claim 1 , wherein
 the heat exchange means for refrigerant condensation comprises first and second heat exchangers for refrigerant condensation provided in series in the middle of the bypass passage and a third heat exchanger configured to evaporate the refrigerant inflated by the second inflation and depressurization means by absorbing heat from the refrigerant condensed by the second heat exchanger.   
     
     
         3 . A vehicle air conditioning device according to  claim 1 , wherein
 the water heat exchanger is provided in the middle of a passage through which the cooling water flows into the heater core.   
     
     
         4 . A vehicle air conditioning device according to  claim 1 , wherein
 the water heat exchanger is provided in the middle of a passage through which the cooling water flows from the heater core.   
     
     
         5 . A vehicle air conditioning device according to  claim 1 , wherein:
 the water heat exchange means comprises a first water heat exchanger provided in the middle of the passage through which cooling water flows into the heater core and a second water heat exchanger provided in the middle of the passage through which cooling water flows from the heater core; and   the first external heat exchanger is disposed between the first and second water heat exchangers.   
     
     
         6 . A vehicle air conditioning device according to  claim 2 , wherein
 the second and third heat exchangers are integrally connected with each other to be heat exchangeable.   
     
     
         7 . A vehicle air conditioning device according to  claim 1 , wherein:
 the heat exchange means for refrigerant condensation comprises first and second heat exchangers for refrigerant condensation provided in series in the middle of the bypass passage, and a third heat exchanger configured to absorb heat from the refrigerant condensed by the second heat exchanger to evaporate the refrigerant inflated by the second inflation and depressurization means;   the water heat exchange means comprises a water heat exchanger to flow engine cooling water which flows between an engine water, jacket and the heater core;   the first heat exchanger is configured to be able to heat the engine cooling water in the water heat exchanger;   a switching element is provided to switch among a first flow from the condenser and the first inflation and depressurization means, a second flow from the first to second heat exchangers, and a third flow from the first heat exchanger to the first inflation and depressurization means.   
     
     
         8 . A vehicle air conditioning device according to  claim 7 , wherein
 the switching element is disposed in the middle of a first passage between the condenser and the first inflation and depressurization means and a second passage from the first to second heat exchangers.   
     
     
         9 . A vehicle air conditioning device according to either  claim 7 , wherein
 the water heat exchanger is provided in the middle of the passage through which cooling water flows from the engine water jacket to the heater core.   
     
     
         10 . A vehicle air conditioning device according to  claim 7 , wherein
 the third heat exchanger is integrally provided with the second heat exchanger.   
     
     
         11 . A vehicle air conditioning device according to  claim 7 , wherein
 the water heat exchange means comprises a first water heat exchanger provided in the middle of the passage through which cooling water flows from the water jacket to the heater core and a second water heat exchanger provided in the middle of the passage through which cooling water flows from the heater core to the water jacket;   the engine cooling water in the first water heat exchanger is heatable by the first heat exchanger for refrigerant condensation, and the cooling water in the second heat exchanger is able to heat the refrigerant in the second heat exchanger for refrigerant condensation;   a third passage through which a first passage between the condenser and the first inflation and depressurization means and a second passage from the first to second heat exchangers communicate with each other is additionally provided; and   the switching element includes a first switching element disposed between the middle of the first passage and the third passage and a second switching element disposed between the middle of the second passage and the third passage.   
     
     
         12 . A vehicle air conditioning device according to  claim 1 , wherein
 the heat exchange means for refrigerant condensation comprises a first heat exchanger for refrigerant condensation provided in series in the middle of the bypass passage and a second heat exchanger configured to absorb heat from the refrigerant condensed by the first heat exchanger to evaporate the refrigerant inflated by the second inflation and depressurization means;   the water heat exchange means comprises a water heat exchanger to flow engine cooling water which flows between an engine water jacket and the heater core; and   the water heat exchanger is disposed between the first and second heat exchangers.   
     
     
         13 . A vehicle air conditioning device according to  claim 12 , wherein
 the engine cooling water flowing in the water heat exchanger flows from the water jacket to the heater core.   
     
     
         14 . A vehicle air conditioning device according to  claim 12 , wherein
 the engine cooling water flowing in the water heat exchanger flows from the heater core to the water jacket.   
     
     
         15 . A vehicle air conditioning device according to  claim 1 , wherein
 the heat exchange means for refrigerant condensation comprises a first heat exchanger for refrigerant condensation provided in series in the middle of the bypass passage and a second heat exchanger configured to absorb heat from the refrigerant condensed by the first heat exchanger to evaporate the refrigerant inflated by the second inflation and depressurization means;   the water heat exchange means comprises a first water heat exchanger to flow engine cooling water which flows from an engine water jacket to the heater core and a second water heat exchanger to flow engine cooling water which flows from the heater core to the engine water jacket; and   the first heat exchanger is disposed between the first and second water heat exchangers and the second water heat exchanger is disposed between the first and second at exchange means.